Fred Warmbier said he was stunned when told of his son's condition one week ago.
American University of Virginia student Otto Warmbier, who was detained for 17 months in North Korea and suffered a serious neurological injury was "brutalized" by the reclusive regime, his father said on Thursday.
"Disbelief. Couldn't sit down. I don't know what being in shock is, but I'm pretty sure I was," he said, referring to being informed Otto Warmbier was in a coma.
Despite the "severe" injury, 22-year-old Warmbier is stable and receiving treatment at the University of Cincinnati Medical Center, center spokeswoman Kelly Martin said at a news briefing at Warmbier's high school in Wyoming, Ohio.
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Doctors are scheduled to provide further details about Warmbier's condition on Thursday afternoon.
Warmbier has been in a coma since March 2016, shortly after he was sentenced to 15 years of hard labor in North Korea, the family said on Tuesday after he was released.
"We don't believe anything they (North Korea) say," said Fred Warmbier, who was wearing a sport coat that Otto Warmbier had worn during a confession to his crimes last year in North Korea that was broadcast.
The New York Times previously cited a senior U.S. official as saying Washington had received intelligence reports Warmbier was repeatedly beaten while in North Korean custody.
Fred Warmbier said of his son's release: "They did not do this out of the kindness of their hearts."
"North Korea does not do anything out of the kindness of their hearts," he added.
Ohio Senator Rob Portman called the North Korean government's handling of Warmbier "abhorrent" in an interview with Fox News.
RELATED: Otto Warmbier, North Korea sentences US student to 15 years of hard labor
"Now we know why they wouldn't allow consular access," he said. "It's a real tragedy."
U.S. President Donald Trump spoke to Fred Warmbier on Wednesday night, Warmbier said. Trump discussed how U.S. Secretary of State Rex Tillerson and Joseph Yun, the U.S. State Department's special envoy on North Korea, worked together to help secure Otto's release, Warmbier said.
Fred Warmbier praised the Trump administration's handling of the situation. Asked if the administration of former President Barack Obama had done enough to secure their son's release, Warmbier said: "The results speak for themselves."
(Writing by Timothy Mclaughlin in Chicago; Additional reporting by Jon Herskovitz in Austin, Texas; Editing by Bernadette Baum)
Christina Gregg contributed to this report.